One of the most common tools found in modern medicine is the intravenous fluid bag or IV bag. These bags are used to dispense medicine and fluids (e.g., water, saline solution, etc.) under many different conditions. Originally, IV "bags" were glass bottles. Modern bags are made of soft plastic. Traditionally, gravity has been used to drain the fluid from the bag. The common view of an IV bag suspended from a pole above a patient's bed is a familiar sight. Pictures of soldiers holding IV bags over wounded soldiers are also a common sight. Pictures of soldiers holding IV bags over wounded soldiers are also a common sight. Therein lies the problem with these bags. There is no practical way to drain the standard IV bag without gravity or a mechanical pump. In combat, this is an especially serious problem because it requires a person to do nothing but hold a bag. The same is true for paramedics, who are forced to work frequently in field conditions.
Mechanical pumps now exist to drain bags, but these are operated electrically and are most convenient in a hospital setting. Moreover, pumps must be monitored to ensure that proper dosages and fluid flows are maintained. The level of maintenance for these pumps is often little improvement over the standard gravity bags. Also, IV pumps are expensive.
The present invention overcomes these difficulties. It consists of a double walled envelope that evacuates the fluid within the envelopes by pressure waves. The action of the pressure waves operates on the fluid regardless of the position of the IV envelope. Thus, the envelope can be set down on a stretcher or on the patient and the product will still be delivered. It is important to understand that this double walled envelope is not a "bag within a bag". A bag within a bag design would have an inner product bag that is surrounded by an outer pressure bag. It is true that as air pressure is forced into the outer bag, the pressure created forces product from the inner bag. The problem with this design, however, is that in many positions, the inner bag is choked off by the pressure in the outer bag before all of the product can be removed. This is because the inner and outer bags are not connected completely around their perimeters, air is free to move around the inner bag, moving it away from the walls of the outer bag which often squeezes the outlet valve, shutting down the flow of fluid.
In the present invention, the IV envelope system is formed by creating an inner product containment envelope that is covered on all sides by outer pressure envelope. The seams of both the inner and outer envelopes are sealed together along their perimeters resulting in the outer envelopes forming two walls around the inner product envelope.
An outlet port is provided for the product containment envelope for removal of the fluids. This outlet port is similar to those found on common IV bags. A second pressure entry port is provided opposite to the outlet port. The second entry port is in communication with both outer pressure envelopes. Thus, as pressure is induced into the pressure entry port, product will be forced out of the outlet port once it is opened. As pressure is added to the outer envelopes directionally, the inner envelope will be compressed and will continuously force product out the envelope out until it is evacuated. Because pressure is being supplied to the outer envelopes uniformly, product will be forced out of the inner envelope regardless of the position of the invention. Thus, the IV envelope can be placed horizontally and fluid will still flow as long as pressure is maintained in the outer envelopes.
Because the inner product envelope is connected to the outer envelopes continuously along the seams, it cannot separate and collapse while leaving product in the inner envelope, which can occur with a "bag within a bag" design.
It is an object of this invention to produce an IV system that can operate at all angles.
It is another object of this invention to produce an IV system that can operate without gravity feed.
It is yet another object of this invention to produce an IV system that can operate at all aspects.
It is as yet another object of this invention to produce an IV system that can operate in all types of weather conditions.